Background art of the present technical field includes Japanese Patent Laid-Open No. 2010-238209 (Patent Literature 1). The following is described in this publication. “A center includes a cautious traveling location DB associating and storing information of environments in which vehicles are driven and information of cautious traveling locations where the vehicles need to travel with caution. An on-vehicle device acquires and transmits positional information and environmental information of a vehicle to the center. The center specifies, from the cautious traveling location DB, the cautious traveling location information corresponding to the positional information and the environmental information received from the on-vehicle device and distributes the cautious traveling location information to the on-vehicle device. The on-vehicle device notifies a driver of the cautious traveling location information distributed from the center by displaying the cautious traveling location information on a display or by outputting reading voice from a speaker.”